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281.
Larry Larsen Terri Morrell Gretchen Schalge Meghan Gallione Joseph Bell Kip Petersen Frederick Steiner 《Environmental management》1991,15(4):549-563
This article is the third in a series prepared to explain the Teller County growth management planning process. Once it was
determined by local decision-makers that Teller County, Colorado, would pursue a policy of directed growth, concepts based
on this policy were developed. These concepts presented visions and options for the future. Landscape plans then were developed
for Teller County and the City of Woodland Park planning area so that these options could be visualized by local leaders and
the public. The landscape plans were used as part of the ongoing citizen involvement process to inform the public about the
options for growth management. To provide even more information, detailed designs were developed for specific areas in the
county. From the landscape plan, public involvement effort, and detailed designs, specific implementation measures were identified,
discussed, and adopted. These measures included guidelines for administration, so that county and city goals could be linked
to the actual day-to-day management of development proposals.
Paper 3 in a series of 3. 相似文献
282.
Sylvie Bourthoumieu Francoise Esclaire Faraj Terro Maryse Fiorenza Jean-Luc Eyraud Michel Servaud Muriel Cantaloube Veronique Fermeaux Catherine Yardin 《黑龙江环境通报》2004,24(3):219-223
We describe two cases of sonographic abnormalities associated with unusual chromosomal aberrations. Case 1 presented with a cystic hygroma at 12 weeks' gestation. Cytogenetic analysis revealed an unbalanced complex chromosome rearrangement implicating chromosomes 6, 13 and 21 (karyotype: 47,XX,t(6;21;14)(q14;q21;q21)mat,+21) and corresponding to a complete trisomy 21. This anomaly resulted from malsegregation of a maternal balanced three-way translocation. For case 2, an alobar holoprosencephaly was identified by ultrasonography at 23 weeks' gestation. Chromosomal analysis showed a recombinant rec (13), dup q chromosome, secondary to unequal crossing-over of a paternal pericentric inversion of chromosome 13, giving rise to partial trisomy 13q (karyotype: 46,XX,rec(13)dup(13q)inv(13)(p11q21)pat). These two cases illustrate the role of ultrasound in leading to detection not only of foetal chromosomal aberrations but also of rare balanced chromosomal rearrangements presented by one of the two parents. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
283.
There are two predominant views of organizational commitment: instrumental and affective. The purpose of the paper is to explore the extent to which an adapted version of Etzioni's macro organizational model of involvement may serve as a single model of both affective and instrumental perspectives of organizational commitment. Moral commitment and alienative commitment are treated as affective forms of organizational attachment, and calculative commitment is treated as an instrumental form of organizational attachment. The paper employs five samples for the investigation. It develops scales for measuring each of the three dimensions of commitment. The paper concludes that organizational commitment is multidimensional. It also concludes that employees report a mixture of commitment types. Evidence is offered in support of the affective character of moral and alienative commitment. Although the evidence is equivocal, there is support for the independence of the two dimensions of affective commitment: moral and alienative. Evidence is also offered for the differential association of the three dimensions of organizational commitment with related aspects of organizational behavior. The paper extends our understanding of organizational commitment by providing a place for both instrumental and affective forms of psychological attachment to organizations. It offers scales which may be used for future research, and it suggests research which may extend the adapted model in this paper as well as provide direction for practising managers. 相似文献
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286.
The expectation of elevated 222Rn levels in modern homes that have low air interchange rates with the outdoor air caused us to survey both solar and conventional homes in northeastern New York State. As a group, homes that are more airtight have three times the 222Rn levels of the conventional homes; they have other specific problems that are introduced or exaggerated by modern construction. For example, the highest two levels of radon in the solar homes give doses over 30 years that are known to produce lung cancer in 1% of uranium miners. Summer readings in more than one-half of the cases are different from winter ones by a factor of two or more, so that year-round measurements are necessary for precise dosimetry. The track-etching technique is ideally suited for such measurements. Radon emanation measurements on soils and sand demonstrate a considerable variety of release rates. 相似文献
287.
Comparing Forecasts of the Global Impacts of Climate Change 总被引:2,自引:0,他引:2
Mendelsohn Robert Williams Larry 《Mitigation and Adaptation Strategies for Global Change》2004,9(4):315-333
This paper utilizes the predictions ofseveral Atmosphere-Ocean GeneralCirculation Models and the Global ImpactModel to create forecasts of the globalmarket impacts from climate change. Theforecasts of market impacts in 2100 varyconsiderably depending on climate scenariosand climate impact sensitivity. The modelsdo concur that tropical nations will behurt, temperate nations will be barelyaffected, and high latitude nations willbenefit. Although the size of theseeffects varies a great deal across models,the beneficial and harmful effects areoffsetting, so that the net impact on theglobe is relatively small in almost alloutcomes. Looking only at market impacts,the forecasts suggest that while the globalnet benefits of abatement are small, thedistribution of damages suggests a largeequity problem that could be addressedthrough a compensation program. The largeuncertainty surrounding these forecastsfurther suggests that continued monitoringof both the climate and impacts isworthwhile. 相似文献
288.
This work is concerned with the dynamic modelling of the papermaking section of an integrated newsprint mill, and the subsequent application of two direct search methods in a proof-of-concept optimization study of broke recirculation strategies. The effect of the current broke recirculation policy on the mixed pulp properties at the paper machine headboxes was quantified using a dynamic simulation generating data for an objective function which reflected the rate of change in measurable (flow, consistency and temperature) and immeasurable (total dissolved solids and fibre length distribution) parameters. Genetic Algorithm and the Nelder–Mead simplex methods were then linked dynamically to the simulation and used to find improved ways of recirculating broke pulp. Specifically, the profile of the changes to the broke ratio was modelled using a quadratic function and a second-order transfer function, and the coefficients of these functions were optimized. The optimized broke recirculation resulted in a significant reduction in the value of the objective function, thus, suggesting that the fluctuations in the properties of the mixed pulp stream could be dampened and paper machine headbox stability improved. It is expected that this process enhancement strategy would contribute to an increase in production yield (via a reduction in the occurrence of paper machine breaks), and thus an overall reduction in the waste of materials and energy. 相似文献
289.
290.
The City of Austin, Texas, is one of the fastest growing metropolitan areas in the United States. It is also in one of the most biologically diverse terrestrial ecosystems in the world: the Balcones Canyonlands. Five cave invertebrates and two species of birds that inhabit the area are listed as threatened or endangered, two species of plants are candidates for listing, several others are considered rare and of concern, and a species of the salamander has also been proposed for listing. A habitat conservation plan, of national significance according to Secretary of Interior Bruce Babbit (Haurwitz 1996), has been under development for the last several years to conserve those endangered species through a 2400-ha system of preserves and to allow development to continue in more than 162,000 ha of surrounding area. The preserve system, comprising several units ranging in size from less than a hundred to several thousand hectares, would be bordered in many instances by developed areas. Development and maintenance of the infrastructure necessary for new and existing development, both commercial and residential, could have negated the biological value of the preserves (e.g., power-line corridors, water-treatment pipelines and facilities). The challenge of bringing this plan to fruition illustrates the complex biological, technical, and sociological context within which habitat conservation planning may occur. Resolving resource use conflicts of this nature have several commonalities that overarch these contexts. If recognized and addressed, one may move easily and foster positive results. These commonalities can be expressed as principles such as: relying on scientists to recognize, but not solve problems; acting before a scientific consensus is achieved; including human motivation and responses as part of the system to be studied and managed; and confronting uncertainty. 相似文献